This invention relates to a rivet for fastening a first part to a second part and, more particularly, to a rivet which includes a head portion engaging one side of the first part, a cylindrical shoulder portion extending through an opening in the first part, and a tenon portion projecting through and beyond a hole in the second part. Axially opposed forming tools engage the rivet and the metal of the tenon portion flows to form an enlargement so that the two parts are fastened together between the head portion and the enlargement.